JPH0527785Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Field of Application] This invention relates to a switch, and particularly to a small position detection switch.

[Problems to be solved by the conventional technology and invention] This type of conventional switch will be explained with reference to FIG. 8 of the vertically attached drawings. 1 is a switch case molded from resin. This switch case 1 has an actuator 2 integrally molded with resin installed obliquely from one end of the upper surface to the other end, and the actuator 2 maintains the obliquely installed state by elastic restoring force. It is designed so that it can be done. Further, the switch body 1 has a normally closed terminal NC, a normally open terminal NO, and a common terminal COM protruding from the switch body 1.
The contact piece 3 connected to NC is the switch case 1
The common terminal is fixed in a protruding manner.
A contact piece 4 connected to COM and a contact piece 5 connected to the normally open terminal NO are fixed to the bottom of the main body 1. Therefore, the common terminal
COM is placed on the right side in the figure, and the normally closed terminal NC is placed on the left side. The normally open terminal NO is disposed at an intermediate portion thereof. Therefore, the common terminal
A plate spring 6 that also serves as a movable contact piece is attached to the fixed contact piece 4 of the COM.
One end of the plate spring 6 is fixed, and a movable contact 6a fixed to the tip of the plate spring 6 is connected to a contact 3a provided at the end of the fixed contact piece 3 of the normally closed terminal NC. It is elastically biased in an oblique state so that it can be pressed into contact at all times. Therefore, in this state, the fixed contact piece 5 of the normally open terminal NO and the contact point 6a of the leaf spring 6, which is the movable contact piece, are in an open state. Therefore, the lower end portion is attached to the plate spring 6.
The upper part of the slider 7 which is in contact with the upper surface thereof is made to protrude above the switch case 1, and its upper end surface is in contact with the lower surface of the actuator 2. The switch has mounting holes 8, 8 and is commonly called a small position detection switch with mounting holes.

As mentioned above, the switch is composed of the leaf spring 6, this contact 6a, the contact piece 3 and contact 3a of the normally closed terminal NC, the slider 7, etc., so in this case, the upper actuator 2 is pressed. Lower the slider 7 to turn off the contact 3a of the normally closed terminal NC,
When the contact 5a of the normally open terminal NO is turned on, since the contact timing is based on the leaf spring method as described above, a hysteretic movement peculiar to the leaf spring occurs, resulting in large variations in the contact timing. Furthermore, the contact point has a defect in that stable contact cannot be maintained unless a contact point is used, resulting in high cost. Therefore, to overcome these defects and eliminate the variation in the contact timing,
In order to propose a switch that can also contribute to cost reduction, technical problems arise that must be solved.

[Means for solving problems]

This idea was proposed in order to solve the above problems, and consists of a fixed contact piece fixed inside a switch case molded of resin, etc., and a movable switch that connects and disconnects from the fixed contact piece. In a switch which is provided with a contact point and configured such that the movable contact point can be connected to and disconnected from the fixed contact piece by the sliding action of a slider, the slider projects outside the switch case and can be moved in and out by an actuator. It consists of a protrusion and a body part for fixing the movable contact piece, and the body part extends in the lateral direction so that its side surface can be brought close to the inner surface of the switch case,
The movable contact piece is fixed to the surface of the body so as to be substantially parallel to the front surface of the switch case, and a coil spring is interposed between the lower part of the body and the lower part inside the switch case. To provide a switch, wherein the slider is always urged upward, and a normally open terminal disposed between a normally closed terminal and a common terminal is provided immediately after the coil spring. It is something.

[Effect]

In this invention, since the slider and the movable contact piece are integrally provided, when the protrusion of the slider is pressed by the actuator, the sliding movement of the slider corresponding to the pressing force immediately moves the movable contact piece. Since the fixed contact piece can be turned on and off, the problem of variation in contact timing and hysteresis caused by the plate spring method, which was conventional, could be solved. Furthermore, conventionally a plate spring is used, but this plate spring is easily damaged, whereas the present invention uses a coil spring, which maintains a long life and does not necessarily require the use of contacts. It can also contribute to cost reduction.

Furthermore, since the movable contact piece is fixed to the surface of the body of the slider substantially parallel to the front surface of the switch case, the body of the slider extends laterally with its side surface close to the inner surface of the switch case. As a result, the slider slides while being guided by the inner surface of the switch case. Therefore, the slider also serves as a guide mechanism to prevent wobbling during a switching operation. Furthermore, since the normally open terminal is disposed immediately after the coil spring, the switch itself can be made smaller.

〔Example〕

An embodiment of this invention will be described below in detail with reference to the accompanying drawings. 10 is a switch case molded from resin or the like. As shown in the longitudinal sectional front view of FIG. 4, this switch case 10 has a normally closed terminal NC protruding from the left side, a common terminal COM protruding from the right side, and a normally open terminal NO between them. It is installed protrudingly. Furthermore, the contact piece 11 is connected and fixed to the normally closed terminal NC, and the contact part 11
a is fixed to the left side of the upper end inside the switch body 10. Further, the contact piece 12 of the common terminal COM is fixed to the right side inside the switch case 10,
Moreover, this contact point contact portion 12a is provided vertically and long. Therefore, normally the normally closed terminal
The contact contact portion 11a of the NC and the contact portion 13a at one end of the movable contact piece 13, which will be described later, contact each other to close the contact. Other contact part 1
The contact is closed by contacting 3b and 13b, and the normally closed terminal NC and common terminal are connected.
COM is normally closed. Further, a normally open terminal NO is provided at an intermediate portion between the normally closed terminal NC and the common terminal COM, and
The contact piece 14 is provided and fixed at an intermediate portion between the contact piece 11 of the normally closed terminal NC and the contact piece 12 of the common terminal COM. Then, the contact piece 1
Reference numeral 4 denotes a portion approximately halfway between the upper and lower sides of the switch case 10, which is bent to the left in FIG.
4a. Although each terminal, its contact piece, and contact contact portion are integrally formed by punching a single metal plate, the present invention is not limited thereto.

Next, the slider 15 and the movable contact piece 13 will be explained. As shown in FIG. 7, the slider 15 is molded from resin and has a protrusion 15 at its upper center.
A is provided protrudingly. This protrusion 15a is inserted into a sliding hole 10a opened in the upper center of the switch case 10 so as to be freely retractable. Furthermore, the slider 15
Movable contact pieces 13 integrally formed in the shape of a dragonfly are attached to the body portion 15b with vertically different phases. Although the method of attaching the movable contact piece 13 should not be particularly limited, in this embodiment, the center portion of the movable contact piece 13 is attached to the center portion of the body portion 15b of the slider 15. fixed, and
Each end of the movable contact piece 13 is spaced apart from the body 15b of the slider 15 to serve as a contact contact portion, and the elasticity of the movable contact piece 13 allows the respective fixed contact pieces 11, 12, 14 to Each contact contact part 11a, 12
It is formed so that it can come into elastic contact with a and 14a.
Further, as shown by the chain line in FIG. 4, the upper left tip portion of the dragonfly-shaped movable contact piece 13 is a contact contact portion 13a that comes into elastic contact with the normally closed terminal NC side of the movable contact piece 13, and forms a normally closed contact. do. However, when the movable contact piece 13 moves downward, the normally closed terminal NC side becomes open, and the lower left tip of the movable contact piece 13 comes into contact with the contact contact portion 14a of the normally open terminal NO side. It becomes part 13c. Furthermore, in the same figure, the movable contact piece 13
The contact contact portions 13b, 13b at the upper and lower ends of the right side are contact contact portions that are constantly connected to the common terminal COM. That is, regardless of the vertical movement of the movable contact piece 13, the contact contact portions 13b, 13b are always connected to the common terminal COM. Although the movable contact piece 13 is formed in the shape of a dragonfly as described above, it is not limited to this shape. However, the normally closed terminal NC side is configured to be closed at all times, and when the movable contact piece 13 is lowered, the normally closed terminal NC side is open and the normally open terminal NO side is closed. Furthermore, when the movable contact piece 13 returns upward from the lowered position, the normally open terminal NO side should be open and the normally closed terminal NC side should be closed, forming a normally closed contact. Therefore, a projecting piece 15c is provided at the center of the lower surface of the slider 15 to which the movable contact piece 13 is integrally fixed, and further,
Switch case 1 in a position facing the protruding piece 15c
A recess 10b is provided on the inner side of the lower bottom of the slider 1, and a coil spring 16 is interposed between the recess 10b and the protrusion 15c to urge the slider 15 upward. Furthermore, the protrusion 15a on the upper part of the slider 15 is connected to the switch case 10 as described above.
It is inserted into the sliding hole 10a from the inside toward the outside, and is always projected upward by the bias of the coil spring 16. Therefore, this protrusion 15
An actuator 17, which is pressed into contact with the protrusion 15a from above, is provided diagonally from one side edge of the cover 18 in order to retract the protruding state of the cover 18 from above. Although the actuator 17 and the cover 18 are integrally molded from resin, this is not particularly limited. Further, the cover 18 covers the front opening of the switch case 10. Moreover, engagement holes 18a, 18a are provided on both sides of the engagement holes 18a, 18a.
The cover 18a is engaged with engagement protrusions 10c provided on both sides of the switch case 10 to attach the cover 18 to the switch case 10 to prevent it from accidentally coming off. Moreover, the actuator 17
is elastically biased to maintain the diagonal direction when integrally molded with the cover 18 as described above, but it constantly contacts the protrusion 15a of the slider 15 and transfers the pressing force of other objects to the protrusion. 15a to lower the slider 15 in the switch case 10 by overcoming the pressing force of the coil spring 16, or by releasing the pressing force of the other object, the pressing force of the coil spring 16 is reduced. It is sufficient that the slider 15 is elastically biased enough to return to its original upper position.

Since the above-mentioned embodiment of this invention has the above-mentioned configuration, the slider 15 is connected to the coil spring 1.
6, the protrusion 15a of the slider 15 protrudes upward from the switch case 10 and comes into contact with the lower surface of the actuator 17. At this time, the contact contact portion 13 at one end of the movable contact piece 13 fixed to the slider 15
a is the contact part 1 of the normally closed contact piece NC
Connected to 1a. At this time, the common terminal COM
is the contact contact portion 13 at the other end of the movable contact piece 13.
b, 13b are always connected. Therefore, when the actuator 17 is lowered by the pressing force of another object,
The protrusion 15a of the slider 15 is pressed down to lower it. At this time, the movable contact piece 13 fixed to the slider 15 also descends at the same time.
Therefore, by moving the movable contact piece 13 downward, the contact of the normally closed terminal NC side is turned off.
Then, the contact of the normally open terminal NO side is turned on. At this time, it is a matter of course that the contact on the common terminal COM side is also turned on. Thus,
Operates as a position detection switch. Further, when the pressing force of the actuator 17 is released, the movable contact piece 13 also moves upward and returns to its original position, and the normally closed terminal NC side becomes a contact point.

[Effect of idea]

In this invention, as described in detail in the above-mentioned embodiment, since the movable contact piece is fixed to the slider, the movement of the slider and the movement of the contact point of the movable contact piece are the same. Therefore, by pressing the actuator, the movable contact piece fixed to the slider is moved to adjust the contact timing.
This variation has been eliminated, and the problem of hysteresis peculiar to the conventional plate spring method has been resolved. Furthermore, since a coil spring is used for return, it has a long life, and since it is not necessarily necessary to use contacts, it can also contribute to cost reduction.

Furthermore, since the movable contact piece is fixed to the surface of the body of the slider substantially parallel to the front surface of the switch case, the body of the slider extends laterally with its side surface close to the inner surface of the switch case. As a result, the slider slides while being guided by the inner surface of the switch case. Therefore, the slider also serves as a guide mechanism to prevent wobbling during a switching operation. Furthermore, since the normally open terminal is disposed immediately after the coil spring, the switch itself can be made smaller.

[Brief explanation of drawings]

1 to 7 show an embodiment of the present invention,
Figure 1 is its front view, Figure 2 is its left side view, and Figure 3 is its front view.
The figures are a sectional view taken along line A-A in Figure 2, Figure 4 is a front view with the cover and slider removed, Figure 5 is a front view of the cover, and Figure 6 is a perspective view of the same as seen from the back side.
Figure 7 is a perspective view of the slider and movable contact piece, Figure 8
The figure is a partially cutaway front view showing a conventional switch. Code explanation, 10...Switch case, 10b...
...Recessed portion, 11, 12, 14... Fixed contact piece, 13...
...Movable contact piece, 15...Slider, 15a...Protrusion, 16...Coil spring, 17...Actuator, NC...Normally closed terminal, COM
...Common terminal, NO...Normally open terminal.

Claims (1)

[Scope of utility model registration request] A fixed contact piece is fixed in a switch case molded of resin or the like, and a movable contact that connects and disconnects to the fixed contact piece is provided, and the movable contact is connected to the fixed contact piece by the sliding action of a slider. In the switch configured to be able to connect and disconnect, the slider includes a protrusion that protrudes outside the switch case and can be moved in and out by an actuator, and a body for fixing a movable contact piece; The portion extends in the lateral direction so that its side surface can be brought close to the inner surface of the switch case, and the movable contact piece is fixed to the surface of the body portion substantially parallel to the front surface of the switch case, and further,
A coil spring is interposed between the lower part of the body and the lower part of the inside of the switch case, and the coil spring always urges the slider upward, and the coil spring is inserted between the normally closed terminal and the common terminal. A switch characterized in that the normally open terminal provided is provided immediately after the coil spring.